Underreamer



Feb. 19 1924.

J. M. KELLERMAN UNDERREAMER Y Filed Feb. 18, 1922 Z0 nfuwtofc MSMKBLLBRMH llllatenteollti1 eb. lg, i924.

will@ TTS llpg@ NDEBRER.

9 p `l l Application led February 1S, i922.- Serial No. 537,635.

To all whom t may concer/n:

Be it known that l, JAMES M. KELLERMAN, a citizen of the United States, residing at Los Angeles, in the county of Los Angeles and State of California have invented certain new and useful improvements in Underreamers, of which the 4following is a specilication.

My invention relates to underreamers and more particularly to underreamers for rotary work; and the object is to provide operating blades for underreaming for cooperating with or aiding the standard drilling tools when a well is drilled down to water or clay or producing sands. Another advantage is that the number of strings of casing maybe reduced so that there will be a considerable saving in the cost of the casing. The same results may be accomplished as could be accomplished with standard drilling tools-but the results can be accomplished much quicker. @ther objects and advantages will be fully .explained in the following description and the invention will be more particularly pointed out in the claims. Reference is had to the accompanying drawings which form a part of this application.

Fig. l is a side elevation of the underreamer carrier. Fig. 2 is a vertical section of the same, showing the means for actuating the blades. Fig. 3 is a horizontal section of the carrier, taken on the line 3-3 of Fig. 1. Fig. 4 is a vertical section of an underreamer carrier which has certain parts varying rom the parts shown in the previous views. Fig. 5 is a broken vertical section, showing the means for strengthening the drill pipe stem.

Similar characters of reference are used to indicate the same parts throughout the several views. i

rllhe underreamer is provided with a cylindrical carrier or body member l and this member has cut-outs 2 on opposite sides for the tool wrenches which engage the underreamer. The carrier is threaded at the upper en d 3 for making connection with-the drill stem andthe carrier is threaded interiorly at the lower lend to receive a drill bit 5. 4rlhe carrier has a cylindrical vertical open# ing entirely therethrough for the passage of water and through which the small tools may pass for expandin the cutting blades 4 or for throwing the lades in operative posi- 6 is placed in the, carrier and tion. A pipe for the water Jor other' serves as a passage liquid and principally for keeping the blades or cutters 4 expanded or in operative position. A blade expander 7 operates through the pipe 6 and has a cone-shaped end 8 for expanding the blades 4 or for actuating the blades 4 to throw the same in position for underreaniing. A convenient tool is used for inserting the expander and for removing the same after the blades have been expanded. Y The pipe 6 is also slightly coneshaped at the lower end engaging the blades 4: When the blades have been properly expanded the expander 7 is removed. The lower end of the pipe 6 will hold the blades AV4 in the expanded or working position. rl`he lower edgegsyof the blades are beveled to form cutting edges. -When the roaming is finished or when it is necessary to remove the blades, a tool, or bull dog spear, is rundown into the pipe 6 for lifting it out of thewell. rlFhe blades 4 will be automatically forced back within the carrier. As lthe carrier is lifted upwardly the beveled portions of' the blades will be brought against the casing shoe (not wardly by the casing shoe. The drill bit 5 is connected to the carrier by screwing the upper end thereof into the threaded opening in the lower end of the carrier. When the underreamer is not being used, the bit 5 is connected directly to the drill stem above (not shown). The bit is provided with removable cutting edges 9. which are \mounted in' slots in the lower end of the bit 5 and riveted therein. IThe blades or cutting edges 9 are made of harder metal., as manganese or chrome steel and may be removed and new cutting edges inserted. v The cutting edges are more ecent than a {ishtail bit and are less expensive `and new cutting edgescan be inserted in much shorter tbime than would be required to sharpen the its.

The underreamer shown in Fig. 4 has a carrier l0 which is similar to the carrier previously. shown. 'lihe carrier l() has, a

statlonary expander 11 which 'may be riveted to the carrier 10. Blades or breakers 12 are provided and slidably mounted on a platform or elevator 13. rl`he breakers 12 project through slots 14 in the carrier 10 and the elevator platform 13 has lugs 15 which project into the slots 14 and these lugs serve as guides for the platform 13. rThe reamers or ably mounted in slots 17 in the carrier l0.4

cutting blades 16-are slidl 80 shown) which is also' beveled and forced inn rlh'e reamers `16 are actuated by the ex pander 18 and this expander is actuated by ,.the spring 19. The spring 19 may seat on' the drill bit 5. 'The drill bit is provided v with an opening 20 for the passage of liquid. The breakers 12 and the cutting blades 16 cannot be expanded for operation until lcollar 22 of the drill pipe.

l lto' be connected to a asses below 'the lower edge of the well casing. The' cuttin blades 16 will be held within the slots`17 y thel well casing against the tension of the spring 19. As soon las the breakers 12 pass below the edge of the well casing,l the spring 19 will press the expander 18 upwardly and the expander will throw the blades 16 in operative position.

The drill stem 21 may be made of pipe. l have provided an improvement in the A beveled ring 23 is placed in the coupling or collar 22 and this ring is placed on the end'of"one pipe section 21 and the other\pipe section 21is screwed into the collar 22 so that the ring 23 is caught in between the v ends 'of the pipe sections 21. The bevel4 of the ring 23 is outward so' that vthe ends of thepipe sections 22 will be prevented from closing inwardly. rlllie ring'23 will tend to force the walls of the pipe sections'outwardly against the collar 22. vlFhiswould strengthen the drill stem.A

What l claim, is,M

1. An underreamer comprising a. carrier drillstem andA having an opening therethrough and radial slots leading from said opening outwardly, cutthe Ycarrier 1.0

ting blades slidably mounted in said slots, Van expander movable vertically in said opening andadapted to actuate 'said blades to throw the same in operative position, and al pipe surrounding said Vexpander for holding said blades inoperative position after said expander is removed.

blades in operative rase/eee 2. An underreamer comprising a carrier provided with a threaded upper end forY connection with a drill stem, and provided with afvertical opening therethrough and radial slots leading from saiduopening-outwardly, cutting blades slidably mounted in said 'slotsl a cone-shaped expander movable vertically in said* opening and provided with a threaded connecting end, and a pipe movable in said opening and surrounding said expander and adapted to hold said position after said expander is removed.

3. An underre'amer comprising a carrier provided with a vertical opening" therethrough and radial Vslots'through the sides, a bit connected to the lower end of said carrien and provided-with hardened steel eutting edges, and means for enlarging the opening made by said bit in a continuous operation consistin erally through sai slots, and an expander 'for throwing said blades in operative posi` tion, and means for locking said blades in operative position after the throwing means has been removed.

4. An underreamer comprising a carrier provided with an opening therethrough and Iprovided with slots-through the sides thereof, blades mounted irl said slots and movable radially through said slots and provided with beveled cutting edges, an 'expander movable vertically in said opening for throwing said blades -in operative position, a pipe surrounding said expander for holding said blades in operative position .after said expander is removed and a bitv carried by with cutting edges detachably connected thereto.

'In testimony whereo l set my hand, this 15th dav of Februar 1922.

JAMES M. ELLERMAN.

of vblades movable latsaid carrier and provided v 

